A CWE-200: Information Exposure vulnerability exists in Modicon Controllers (M340 CPUs, M340 communication modules, Premium CPUs, Premium communication modules, Quantum CPUs, Quantum communication modules - see security notification for specific versions), which could cause the disclosure of FTP hardcoded credentials when using the Web server of the controller on an unsecure network.
https://www.se.com/ww/en/download/document/SEVD-2019-316-02%20/
https://www.schneider-electric.com/ww/en/download/document/SEVD-2019-281-02/